Safety device for vaporizer units



June 5, 1951 Filed Jan. 26, 1946 s. P. JONES SAFETY DEVICE FOR VAPORIZER um'rs 2 Sheets-Sheet 1 why/roe:

Arron/Ks.

Patented June 5, 1951 UNITED STATES PATENT OFFICE.

SAFETY DEVICE FOR VAPGBIZER UNITS Sam P. Jones, Dallas, Tex.

Application January 26, 1946, Serial No. 643,821

14.- Claims. 1

The present invention relates to a safety device for a vaporizer unit. More particularly, it relates to a safety device for use with a vaporizer unit of the type employing such liquid fuels as liquid propane or butane, or a combination of them, wherein means are provided to insure the stopping of the vaporizing operation when the filler mechanism for the liquid supply tank is opened.

Particularly, it is an object of the invention to cut off all flame at the vaporizer during the time the liquid fuel is being supplied to the tank.

A particular object of the invention is to provide a control of the foregoing kind, wherein the filler openin for the main tank is remote from the vaporizer, together with a connection between the filler opening means and the vaporizer to stop the vaporization and tostop all flame at the time the filler mechanism is moved to its open position.

A particular object is to perform the foregoing functions by an electromagnetic valve and especially one that is operated by a thermocouple innmersed in a flame.

A further object is to provide a cut-off as aforesaid, that will fail in safe condition, if it fails.

In the drawings:

Fig. 1 is a side elevation, partly in section, of the mechanism;

Fig. 2 is an end elevation, taken from the left end of Fig. 1;

Fig. 3 is a fragmentary elevation as it appears from the opposite side;

Fig. 4 is an enlarged section of the lower part of the vaporizer unit, showing the connections of the present invention;

Fig. 5 is a transverse section through the safety valve, taken on the line 5-5 of Fig. 4; and

Fig. 6 is a View of the valve itself from Fig. 5, but with the valve shown in released or closed position.

The present vaporizing system is substantially that shown in the copending application, Serial No. 630,786, filed November 26, 1945, by this applicant. In general, it includes a liquid supply tank It, into which the liquid, such as propane, is admitted. It also includes a vaporizer unit i i. The vaporizer unit includes a liquid column, generally indicated at B2, and comprising a vaporizing chamber 93 openin at its top into a standpipe I4. The chamber i3 is connected at its bottom to the tank It] by a suitably valved pipe line 15. The top of the standpipe I4 is connected to the top of the tank it through a line it, there being a combination check valve and flow control valve I! in the line Hi. It will be seen that, when 2 the device is inoperative, th liquid level in the tank It and in the standpipe [4 will be the same through the action of gravity.

The vaporizing chamber I3 is enclosed in a heat supplying member 2E1, having a main gas burner 2| at the bottom thereof. This gas burner is fed by a line 22 connected through a thermostatic valve 23. This thermostatic valve has a bulb 24 located so as to respond to the temperatures generated in the vaporizing chamber and to throttle and cut off th flow of gas to the main burner 2| when the temperature in the chamber 13 attains a certain value.

Gas is supplied to the valve 23 through a line 25 which is fed through a pilot safety 26. The pilot safety is supplied with gas by a line 21 which is preferably connected to the outlet from the column l4, although obviously the fuel. may be supplied from other sources. There is a pilot bypass line 28 leading from the pilot safety valve 29 to a-pilot burner 29. This. pilot burner is located adjacent the main burner 2i.

All of the foregoing structure isv shown in detailin the copending application referred to. It will be understood that this type of vaporizer unit is a type wherein the vaporizer pressure in the column l4 controls the height of liquid in the column l4 and the vaporizer chamber l3, and automatically regulates the amount of gas generated. At the start of any operation of the mechanism employing the gas generated, the gas will first be drawn off from the top of the column M. This may not be sufficient to operate the operated mechanism for the period of time required for the generation of gas to reach its running Value. The withdrawal of gas from the top of the column M will reduce. the pressure in the column relative to the vapor pressure at the top of the tank 15. When this pressure differential attains a certain predetermined value, the valve ll, operating as a check valve, Will open and the vapor at the top of the liquid in the tank ill will then be supplied to the operated mechanism to make up the deficiency. In the meanwhile, the burner 2: will be in operation, and will be pro ducing gas in the column I l by application of heat to the vaporizing chamber l3. As soon as this generation of gas is sufllcient to supply the needs of the operated mechanism, the pressure in the column I 4 will be reestablished and the check valve I 'i will close. In order to prevent the reduction of the vapor pressure in the tank [0 below a predetermined value, the flow control feature of the valve I! will operate to permit the flow of gas from the vaporizer chamber [4 into the tank Ill to maintain the temperature and pressure conditions therein.

If the demand from the operated mechanism is less than the amount of gas generated in the column !4, the pressure in the column I4 will increase above that in the tank It, and, as a result, the height of the liquid within the column I4 will be depressed, the liquid being forced back into the tank. The depression of the height of the liquid down into the vaporizing chamber I3 will reduce the area of contact between the parts of the chamber I3 heated by the burner 2| and the liquid, and thereby will reduce the amount of gas generated. An equilibrium condition will be established in which the amount of gas generated will equal that demanded. This will be true for various demands for the operated mechanism, there being a proper liquid level for each of these demands. If the operated mechanism reduces its demand to a certain minimum, or to zero, the vapor pressure in the column l4 may drive the liquid entirely out of the vaporizing chamber, at which there will be substantially no generation of gas thereat.

' The pilot safety 26 supplies gas to the pilot burner 29 through the line 28. The thermostatic valve 23 may close off the supply of gas to the main burner 2| when the temperature of the vaporizing chamber 13 is sufiicient to generate all of the gas needed without additional flame. This will not cut off the pilot burner, which will continue to operate. As will appear, a failure of combustion at the pilot burner will cause the pilot safety 26 to close.

In gas generators of the present type, it is highly important that there .be no flame means around the entire mechanism at the time the main tank ID is being filled with liquid, owing to the fact that liquid may spill and rapidly vaporize around the location of the flame and ignite. The present invention provides a means to insure that there will be no exposed flame during the filling operation.

To the foregoing end, it will be seen that the tank ID has a cover 3| thereon at a point spaced from the vaporizing chamber H. This hood or cover 3| is hinged at 32 to the tank ll). It covers a filler opening 33, a pressure gauge 34, an equalizing valve 35, and a liquid level gauge 36, which are merely diagrammatically illustrated in Fig. 1. It is necessary to open the hood 3| before access may be had to the filler opening 33.

It will be seen that the hood 3| stands upwardly from the hinge 32. Consequently the top of the hood 3! travels in an arcuate path, as shown in Fig. 2.

The pilot safety valve is shown more in detail in Fig. 5, wherein it will be seen that it includes a housing 38, having an inlet into which the pipe 21 is connected. It also has an outlet side with which the main burner outlet 25 is connected. Between these two, there is a valve seat 39 adapted to be regulated by a valve 43. The pilot line 28 leads out from the housing 38 after the valve seat 39.

The valve includes a stem 4| that extends through a partition wall 42, in which it slides. A coil spring 43, acting between the partition 42 and the valve head 45, normally urges the valve leftward in Fig. into seating position on the valve seat 39.

The partition 42 provides a chamber 45 in the valve housing 39 in which operating means for the valve are provided. The valve stem has a 4 magnetically conducting disc or armature 46 secured to its end within the chamber 45.

The chamber is closed by a fitting 41, preferably of insulating material such as one of the plastics. This fitting is closed across the end, and, at its center, supports a U-shaped magnetic core 48 that is bolted through the head substantially in the manner shown. This magnetic core member has two legs 49 and 50 united by a bight portion, as shown.

The head 41 also has embedded therein two electrical conductors 5| and 52 that project through the walls of the head. The upper conductor 5!, on its inner end, supports one terminal 53 of a coil, generallyindicated at 54. This coil is wrapped around both legs 43 and 50 of the core member 48 in series, and its other terminal 55 is embedded in the member 52.

Near the pilot burner is a thermocouple head 58 containing a thermocouple. A tube 59 encloses the thermocouple leads and is clamped into the two members 5| and 52, with one of the thermocouple wires connected to each of the said members. The head 58 is adapted to be immersed in the pilot flame adjacent the pilot burner 29.

A shunt armature 63 is pivoted at 64 to a bracket 65 supported upon the member 52. A coil spring 66 normally urges the shunting armature 63 counterclockwise in Fig. '5, so that it is in contact with both of the two members 5| and 52 and establishes a free electrical path between them.

This armature 63 receives a cable or wire 68 at its upper end. This wire passes out through the container of the vaporizing chamber and is connected at its upper end to the upper part of the hood 3! on the head of the filler opening means.

It will be seen that the pilot receives gas from the bypass line 23 downstream of the valve 40. When this pilot burner 29 is ignited, it supplies heat to the thermocouple head 58, and a current is thereby generated. When the hood 3| is down, the cable 68 is drawn so that the shunting armature 63 is in the position shown in full lines in Fig. 5, away from the two conductors 5| and 52. As a result, the thermocouple circuit is completed through the conductor ill, the terminal 53 of the coil 54, the coil itself, the terminal 55, the conductor 52 and back to the thermocouple. When the thermocouple is hot, therefore, the coil 54 will be energized and the magnetic field will be set up between the legs 49 and 53 of the magnetic core member, which legs are the poles of a magnet that draw the disc 46 on the valve stem 4| toward them, and thereby open the valve 43 against its coil spring 43. When the valve is open, as shown in Fig. 5, the gas from the main line 21 may flow downwardly past the valve 4lland out the outlet 25 to the thermostatic valve 23, and finally to the burner 2|.

If the pilot burner 29 fails of combustion, the thermocouple '58 will cool, and there will be no current generated thereby. Consequently, the coil 54 will be deenergized, will release the disc 46, and the spring 43 will then close the valve, preventing the flow of gas to the main burner 2!.

When the hood 3| is opened, the cable 62 is slackened by the lateral displacement of the upper part of the hood 3 I. It slackens sufilciently so that the spring 65 may draw the shunting armature G3 to the dotted line position in Fig. 5, in which it shuntsacross between the two coni ductors 5| and 52. This deenergizes the coil? 54 and permits the valve to close, thereupon cutting oii the flow of fuel to the main burner and. the pilot burner, and. ultimately stopping the generation of gas.

When it is desired to. restart the burner mechanisms, heat is supplied to the thermocouple 58, which thereupon generates. current that energizesthemagnetic, ccilti l and draws the valve 40 to its open position. Gas may then flow to, the pilot burner. The pilot burner is ignited, and it thereafter supplies the heat that will produce generation of current by the thermocouple head. Ignition of the mainburner will follow whenever the thermal valve 23 is open.

It will be seen, from the foregoing, that all gas generation is stopped when the hood is open, except for such generation as will continue because of the previous heating of the parts of the vaporizing chamber It. More particularly, all flame is cut oil, so that any highly combustible gases that may be spilled, or may be blown around the flame, can do no harm.

It will also be seen that. the electrical parts are located away from the gas. The magnetic coils are enclosed in the housing. in the chamber 45, separated from the main gas lines. If the cable breaks, the spring 56 will draw the armature 63 across the conductors and will shunt the coil, and the valve will close. This is a desirable safety feature.

What is claimed is:

1. In a vaporizing system for use with volatile liquids, a supply tank, a filler mechanism for introducing liquid thereinto, said mechanism having a movable member, vaporizing means associated with the tank for generating gas from the liquid, liquid passage means between the supply tank and the vaporizer, gas passage means between the supply tank and. the vaporizer, means including a movable device operable from a first to a second position for suppressing operation of the vaporizing means, and energy conducting connections between the movable member and the movable device, for causing movement of the movable memberof the filler mechanism into po. sition to permit the tank to be filled, to effect movement of the movable device of the vaporizer into its second position.

2, In a vaporizing system for use with volatile liquids, a supply tank, a filler mechanism for introducing liquid thereinto, said mechanism having a movable member, vaporizing means associated with the tank for generating gas from the liquid, means for suppressing operation of the vaporizing means including a movable element movable to suppressing position, electrical means including a thermocouple tocontrol movement of the element, and means operated by movement of the movable member of the filler mechanism to cause the electrical. means to effect movement of the movable element to suppressing position when the movable member of the filler mechanism is moved to permit the tank to be filled.

3. In a vaporizing system for use: with volatile liquids, a supply tank, a filler mechanism for introducing liquid thereinto, said mechanism having a movable member, vaporizing means including a primary burner and ignition means for said primary burner associated with the tank for generating gas from the liquid, cut-off means operable to cut ofi said ignition means, and connections between the movable member of the filler mechanism and the cut-off means to eifect movement of said means to cut ofi the ignition 6, means when the movable member is moved to position to permit the tank to be filled,

4. In a vaporizing system for use with volatile liquids, a supply tank, a filler mechanism for introducing liquid thereinto, said. mechanism having a movable member, vaporizing means associated with the tank for generating gas from the liquid, liquid passage means between the supply tank and the vaporizer, gas passage means between the supply tank and the vaporizer, said vaporizing means including a heat supply means to cause vaporization of the liquid, and cut-ofi means torender the heat supply means inoperative including connections between the cut-off means and said member to effect operation of the cut-off means when the movable member of the filler mechanism is moved to permit the tank to be filled.

5. In a vaporizing system for use with volatile liquids, a supply tank, a filler mechanism. for introducing liquid thereinto,. said mechanism having a movable member, vaporizing means associated with the tank for generating gas from the liquid, liquid passage means between the supply tank and the vaporizer, gas passage means between the supply tank and the vaporizer, said vaporizing means including a burner having a fuel supply line, a valve in the line, and means operated by movement of the movable memberof the fillermeehanism to cause closure of the valve and stopping of burner operation when the movable member is moved to permit the tank to be filled.

6. In a vaporizing system for use with volatile liquids, a supply tank, a. filler mechanism tor introducing liquid thereinto, said mechanism having a movable member, vaporizing meansassociated with the tank for generating gas from the liquid, said vaporizing means including a burner having a fuel supply line, a valve in the line, and means operated by movement of the movable member of the filler mechanism to cause closure of the valve and stopping of burner operation when the movable member is moved to permit the tank to be filled, said last-named means includingmagnetic means adapted. to hold the valve open, means to close the valve, and means operated by movement. of the movable member to reduce the power of. the magnetic means below that toholdthetvalve open.

'7". In a vaporizingsystem for use with volatile liquids, a supply tank, a filler mechanism for introducing liquid'thereinto, said mechanism hav ing a movable: member, vaporizing means associated' with the tank for generating. gas from the liquid, said vaporizing means including a burner having aiuel' supply line, a: valve in the line, and means operated by movement of the movable member of thefill'er mechanismtd cause closure of the valve and. stopping of burner 0poration when the movable. member is moved to permit the tank to. be filled, said last-named means including. magnetic means adapted to hold the valve open, means; to close the valve, said magnetic means including a coil, apower source for the coil, and means to short circuit the coil, said short circuiting means being connected to move to short-circuiting position when the movable member of the filler mechanism is moved to position to permit the tank to be filled.

8. In a vaporizing system for use with volatile liquids, a supply tank, a filler mechanism for introducing liquid thereinto, said mechanism having a movable member, vaporizing means associated with the tank for generating gas from the liquid, said vaporizing means including a burner having a fuel supply line, a valve in the line, and means operated by movement of the movable member of the filler mechanism to cause closure of the valve and stopping of burner operation when the movable member is moved to'permit the tank to be filled, said last-named means including magnetic means adapted to hold the valve open, means to close the valve, said magnetic means including a coil, a power source for the coil comprising a thermocouple adapted to be immersed in the burner flame, and means to short circuit the coil, said short-circuiting means being connected to move to short-circuiting position when the movable member of the filler mechanism is moved to position to permit the tank to be filled.

9. In a vaporizing system, a supply tank to hold a volatile liquid, a filler means therefor, a cover over said filler means and movable to render the means accessible for filling the tank, a vaporizer including a chamber to receive liquid from the tank and deliver gas to an outlet, a main burner associated with the vaporizer chamber to heat the same, a pipe between the gas outlet of the vaporizer and the main burner, a pilot burner connected with said pipe, a pilot safety device adapted to cut off the flow through the pipe when the pilot burner fails of combustion, a thermostatic valve controlling flow of gas to the main burner, the pilot safety device including a thermocouple adjacent the pilot burner, a valve in the safety device, a spring for closing the valve, an electromagnetic coil for opening the valve, the coil having terminals spaced from each other and connected with the thermocouple leads, a shortcircuiting member movably supported on the pilot safety device for movement to and from a position bridging the coil terminals, means urging the short-circuiting device into contact with said terminals, and means to withdraw the device from the terminals, said last-named means being operated by movement of the movable cover for the filler means to its closed position.

10. In a vaporizing system, a supply tank, filler means therefor including a movable member requiring movement from a closing to an opening position to enable filling to be performed, vaporizing means associated with the tank to vaporize liquid therefrom, means operable into position to render the vaporizing means inoperative, means normally urging the operatable means into operating position, and means connecting the operating means to the movable member of the filler means to eiIect movement of the operatable means to inoperative position when the movable member is moved to closing position, said urging means being operatable to render the vaporizing means inoperative upon failure of the connections.

11. In a device of the type described, a supply tank; a filler mechanism for introducing liquid into said tank-including a member movable between an open and a closed position; avaporizer; a conduit between the tank and the vaporizer; a main burner for supplying heat to the vaporizer; passage means between the main burner and a supply of combustible material; valve means in said passage means; yieldable means urging the valve means toward the closed position; releasable means holding the valve means in the open position against the action of said yieldable means; and means for releasing said holding means when the movable member is moved to the open position.

12. In a device of the type described, a supply tank; a filler mechanism for introducing liquid into said tank including a member movable between an open and a closed position; a vaporizer; a conduit between the tank and the vaporizer; a main burner for supplying heat to the vaporizer; a pilot burner for supplying ignition for the main burner; passage means between said burners and a supply of combustible material; valve means in said passage means; and means actuating said valve means to close off said passage means When the movable member is moved to the open position or when the temperature of the pilot burner drops below a predetermined value.

13. In a device of the type described, a supply tank; a filler mechanism for introducing liquid into said tank including a member movable beween an open and a closed position; a vaporizer; a conduit between the tank and the vaporizer; a main burner for supplying heat to the vaporizer; a pilot burner for supplying ignition for the main burner; passage means between said burners and a supply of combustible material; valve means in said passage means; yieldable means urging the valve means toward the closed position; and releasable means holding the valve means in the open position against the action of said yieldable means; means for releasing said holding means when the movable member is moved tothe open position; and means for releasing said holding means when the temperature of the pilot burner drops below a predetermined value.

14. In a device of the type described, a supply tank; a filler mechanism for introducing liquid into said tank including a member movable between an open and a closed position; a vaporizer; a conduit between the tank and the vaporizer; a main burner for supplying heat to the vaporizer; a pilot burner for supplying ignition for the main burner; passage means between said burners and a supply of combustible'material; valve means in said passage means; yieldable means urging the valve means toward the closed position; and releasable means including an electromagnet holding the valve means in the open position against the action of said yieldable means; means for releasing said holding means when the movable member is moved to the open position; and means for releasing said holding means when the temperature of the pilot burner drops below a predetermined value.

SAM P. JONES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 282,037 Bean July 31, 1883 296,147 Davis Apr. 1, 1884 

